More recent findings reveal possible parasomnias involving sleep-related behaviors triggered by SDB—in particular, sleepwalking, night terrors, RBD, and sleep-related eating disorder. Further complicating the matter is that sedative/hypnotics can provoke both SDB events and these behavioral parasomnias. Ongoing studies are attempting to untangle these interwoven factors.
Perhaps most intriguing is that SDB events may provoke nightmares, RBD, and sleepwalking episodes. It stands to reason that any choking episode can initially produced intense fear, anxiety, and/or panic. Pagel and Kwiatkowski19 studied nightmares in 400 patients who were also evaluated polysomnographically for SDB. Patients with severe SDB had fewer recalled nightmares than those with milder disease (30% vs 70%, respectively). This may be because patients with severe SDB have reduced REM sleep, are less likely to fully awaken, or have habituated to the awaken-ings with choking and gasping. It would be interesting to see whether this relationship reverses in patients with PTSD, given that severe SDB is associated with increased norepinepherine turnover due to sympathetic nervous system up-regulation in response sleep disturbance.
Sleep problems (and especially nightmares) are cardinal symptoms of PTSD. Our data strongly support an association between SDB and PTSD.5 This association has also been reported by others.20 Krakow and colleagues21 posit an arousal-based mechanism initiated by posttraumatic stress–promoting SDB development in trauma survivors. Of note: continuous PAP treatment of obstructive sleep apnea improved insomnia, nightmares, and PTSD symptoms, which may indicate that causality is bi-directional.21-23
Sleep loss or disturbance, whether associated with SDB or other conditions, can impair an individual’s coping mechanisms. When sleepy, we are easily frustrated and must make more effort to perform otherwise mindless and rote tasks. In patients who already have difficulty in functioning, especially those prone to impatience, anger, panic, and/or denial, the additional stressor of impaired sleep can exceed the capacity of their defense mechanisms. Thus, SDB can create a special vulnerability to psychological problems—especially anxiety.
Attention deficit. Recent studies suggest a relationship between SDB and ADHD in pediatric patients. Findings suggest that many children and adolescents (25% to 50%) with ADHD have sleep problems.24 In attention and hyperactivity among general pediatric patients have been shown to be associated with increased daytime sleepiness, snoring, and other symptoms of SDB.25
Youssef and colleagues26 found a high incidence (20% to 30%) of obstructive sleep apnea in patients with full ADHD syndrome; once obstructive sleep apnea was treated, improvements in behavior, inattention, and overall ADHD were seen. Naseem and colleagues27 reported on 3 patients with adult hyperactivity; all 3 patients suffered from symptoms of obstructive sleep apnea. With continuous PAP, 2 of the 3 patients showed improvement in their sleep and hyperactivity symptoms.
The vast majority of patients with SDB report sleepiness. If the sleepiness level exceeds the individual’s compensatory alertness mechanisms, he may resort to additional strategies to maintain focus (eg, caffeine ingestion). Arousal and attention are fundamental to most cognitive tasks, particularly those that require quick or well-timed responses.28 However, beyond simple attentiveness, diminished executive task abilities (sometimes considered frontal lobe functions) were correlated with sleepiness and, thus by association, with SDB.29
1. Chung F, Yegneswaran B, Liao P, et al. STOP questionnaire: a tool to screen patients for obstructive sleep apnea. 2008. http://sleepmed.com.au/STOP_questionaire.pdf. Accessed April 24, 2012.
2. Ballester E, Badia JR, Hernández L, et al. Evidence of the effectiveness of continuous positive airway pressure in the treatment of sleep apnea/hypopnea syndrome [published correction appears in Am J Respir Crit Care Med. 1999;159(5, pt 1):1688]. Am J Respir Crit Care Med. 1999;159:495-501.
3. Jenkinson C, Davies RJ, Mullins R, Stradling JR. Comparison of therapeutic and subtherapeutic nasal continuous positive airway pressure for obstructive sleep apnoea: a randomised prospective parallel trial. Lancet. 1999;353:2100-2105.
4. Barnes M, Houston D, Worsnop CJ, et al. A randomized controlled trial of continuous positive airway pressure in mild obstructive sleep apnea. Am J Respir Crit Care Med. 2002;165:773-780.
5. Sharafkhaneh A, Giray N, Richardson P, et al. Association of psychiatric disorders and sleep apnea in a large cohort. Sleep. 2005;28:1405-1411.
6. Yue W, Hao W, Liu P, et al. A case-control study on psychological symptoms in sleep apnea-hypopnea syndrome. Can J Psychiatry. 2003;48:318-323.
7. Mosko S, Zetin M, Glen S, et al. Self-reported depressive symptomatology, mood ratings, and treatment outcome in sleep disorders patients. J Clin Psychol. 1989;45:51-60.
8. Pillar G, Lavie P. Psychiatric symptoms in sleep apnea syndrome: effects of gender and respiratory disturbance index. Chest. 1998;114:697-703.
9. Means MK, Lichstein KL, Edinger JD, et al. Changes in depressive symptoms after continuous positive airway pressure treatment for obstructive sleep apnea. Sleep Breath. 2003;7:31-42.
10. Habukawa M, Uchimura N, Kakuma T, et al. Ef-fect of CPAP treatment on residual depressive symptoms in patients with major depression and coexisting sleep apnea: contribution of daytime sleepiness to residual depressive symptoms. Sleep Med. 2010;11:552-557.
11. Day R, Gerhardstein R, Lumley A, et al. The behavioral morbidity of obstructive sleep apnea. Prog Cardiovasc Dis. 1999;41:341-354.
12. Hanania NA, Müllerova H, Locantore NW, et al; Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) Study Investigators. Determinants of depression in the ECLIPSE chronic obstructive pulmonary disease cohort. Am J Respir Crit Care Med. 2011;183:604-611.
13. Baran AS, Richert AC. Obstructive sleep apnea and depression. CNS Spectr. 2003;8:128-134.
14. Ishman SL, Cavey RM, Mettel TL, Gourin CG. Depression, sleepiness, and disease severity in patients with obstructive sleep apnea. Laryngoscope. 2010;120:2331-2335.
15. Millman RP, Fogel BS, McNamara ME, Carlisle CC. Depression as a manifestation of obstructive sleep apnea: reversal with nasal continuous positive airway pressure. J Clin Psychiatry. 1989;50:348-351.
16. Gokcebay N, Hirshkowitz M, Zebrak A, Oksenholt R. Vital exhaustion versus depression in patients with obstructive sleep apnea. Sleep Res. 1997;25:245.
17. Husain AM, Mebust KA, Carwile ST, et al. Depression in sleep disorders clinics. Sleep Breath. 1997;2:73-75.
18. Schenck CH, Bundlie SR, Patterson AL, Mahowald MW. Rapid eye movement sleep behavior disorder. A treatable parasomnia affecting older adults. JAMA. 1987;257:1786-1789.
19. Pagel JF, Kwiatkowski C. The nightmares of sleep apnea: nightmare frequency declines with increasing apnea hypopnea index. J Clin Sleep Med. 2010;6:69-73.
20. Krakow B, Melendrez D, Johnston L, et al. Sleep-disordered breathing, psychiatric distress, and quality of life impairment in sexual assault survivors. J Nerv Ment Dis. 2002;190:442-452.
21. Krakow B, Melendrez D, Pedersen B, et al. Complex insomnia: insomnia and sleep-disordered breathing in a consecutive series of crime victims with nightmares and PTSD. Biol Psychiatry. 2001;49:948-953.
22. Krakow B, Lowry C, Germain A, et al. A retrospective study on improvements in nightmares and post-traumatic stress disorder following treatment for co-morbid sleep-disordered breathing. J Psychosom Res. 2000;49:291-298.
23. Youakim JM, Doghramji K, Schutte SL. Posttraumatic stress disorder and obstructive sleep apnea syndrome. Psychosomatics. 1998;39:168-171.
24. Corkum P, Tannock R, Moldofsky H. Sleep disturbances in children with attention-deficit/hyperactivity disorder. J Am Acad Child Adolesc Psychiatry. 1998;37:637-646.
25. Chervin RD, Archbold KH, Dillon JE, et al. Inattention, hyperactivity, and symptoms of sleep-disordered breathing. Pediatrics. 2002;109:449-456.
26. Youssef NA, Ege M, Angly SS, et al. Is obstructive sleep apnea associated with ADHD? Ann Clin Psychiatry. 2011;23:213-224.
27. Naseem S, Chaudhary B, Collop N. Attention deficit hyperactivity disorder in adults and obstructive sleep apnea. Chest. 2001;119:294-296.
28. Kim H, Dinges DF, Young T. Sleep-disordered breathing and psychomotor vigilance in a community-based sample. Sleep. 2007;30:1309-1316.
29. Naëgelé B, Thouvard V, Pépin JL, et al. Deficits of cognitive executive functions in patients with sleep apnea syndrome. Sleep. 1995;18:43-52.
30. Hirshkowitz M, Mammen MH. Emergent sleep events related to medical treatment. In: Chokroverty S, Sahota P, eds. Acute and Emergent Events in Sleep Disorders. New York: Oxford University Press; 2010.